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46

tl;dr: Yes, all plants breathe.— I'm not sure whether I understand the question correctly; because all plants use respiration! Some of the organic high-energy substances produced by photosynthesis are later "burnt" to produce energy in the same "respiration" process used by animals, producing CO2. The difference to animals is that green plants ...


15

Besides the unicellular organisms cited by other answers (and the fact that plants actually do respiration), there are some animals who are able to get, although indirectly, energy from photosynthesis through symbiosis with photosynthesizing organisms. You can try the spotted salamander Ambystoma maculatum: The spotted salamander is similar to the sea-...


13

Short answer Plants release O2, because it is not an energy source. Instead, it is used to free energy from energy-rich organic compounds. Background Plants are solar powered. They release oxygen as a waste product during carbon fixation. Carbon fixation is basically the storage of solar power into carbon-bonds in glucose, a process referred to as ...


9

As far as I can understand your question, you wish to know why a plant cell consumes ATP to produce glucose when it can directly use the ATP as an energy molecule. ATP is an energy currency and is required in different biochemical pathways. However, it is not a good energy storage molecule. Following are the reasons why production of an energy molecule ...


7

Plants collect energy for themselves via photosynthesis, not for others. It is used for it's own growth and survival. It's energy is then redistributed to other organisms when either the plant dies and decomposes or when it is consumed. Many organism cannot collect their energy like plants do, and thus must feed on organisms (like plants) that are able to ...


7

First of all, for those readers with less knowledge of the general principles of biology, I want to state an important, even if obvious, point: The brain doesn't "prefer" anything. Despite being the smartest organ in the body, it is subjected (like any other biological system) to changes in the concentrations of the substances in question, that is, glucose ...


6

Mushrooms are the fruiting bodies of fungi. Fungi get their energy by decomposing dead or decaying organic material, such as fallen leaves or dung. Some background: spores of fungi germinate forming mycelia consisting of threadlike hyphae. When the hyphae of different fungi meet, they may have sex and form mushrooms. The mushrooms produce the spores. See ...


6

As @canadianer comments, this question is unanswerable, and it verges on being classified as ‘opinion-based’. However, because I do not find the answer from the OP appealing, I’ve set out a few points of my own. Hardly an answer — more a list of alternatives as food for thought. I can imagine adenine being chosen for one of the following reasons (others ...


4

Wikipedia is your friend: Exocytosis... is the durable, energy-consuming process by which a cell directs the contents of secretory vesicles out of the cell membrane and into the extracellular space. and Endocytosis is an energy-using process by which cells absorb molecules (such as proteins) by engulfing them. Emphasis mine. Here's a nifty paper ...


4

It depends, but you're going to die. Specifically, it depends on how fat you are. Even Andreas Munzer is going to die. At only 3% body fat, burning all his fat (9kcal/g) would "only" increase his internal body temperature by 270 degrees C. Factoring in the energy required to boil off his body moisture and adding in body heat leaves Andreas at ~200 C or so (...


4

Indeed several organisms can do both. Another good example following the answer from Prince of an organism that can do both photosynthesis and respiration would be cyanobacteria. Source: Photosynthesis and Respiration in Cyanobacteria


4

One of the reasons why adenine is by far the most common component in energy carriers might be its less utility in DNA. Naitoh (2008) also describes this opinion. Keeping in mind the conditions on earth when first life would have evolved, this becomes easy to conceptualize. Naitoh (2008) compared RNAs of many different species of hyper-thermophiles and found ...


4

Yes, the energy from ATP hydrolysis can vary between different cell types and condition, because it depends on several factors. Hence, you will find different values in various textbooks. First, like any chemical reaction, the free energy $\Delta G$ of ATP hydrolysis depends on the concentrations of the reactants. You can explore different values of $\Delta ...


3

Let's look at a very simple "ecosystem", cows and grass. Imagine there is 1000 kilograms of grass available. This can support about 100 kg of cow. There's your 10% figure, but mass here instead of energy. When the cow eats the grass it must break down the food to get both matter and energy. Everytime energy is transfered, some of it is "lost" as heat. So as ...


3

Oxygen has a high electronegativity, in other terms it really likes electrons. In this scale neon has the highest electronegativity of all elements, followed by fluorine, helium, and oxygen. https://en.wikipedia.org/wiki/Electronegativity#Allen_electronegativity These are redox reactions. In the first reaction carbon was oxidized 0 -> +4 and ...


3

I’m not quite sure which of two questions you are asking here, but as this is basic to understanding metabolism, I think an answer to both questions will be of most general utility, even if you personally already understand the answer to the first. [1] The Gibbs Free Energy Change in a chemical reaction determines whether it will proceed spontaneously If ...


3

The first reaction is catabolism. It does require some energy input in the beginning ("energy investment" of glycolysis) but ultimately leads to net energy release through "energy payoff" of glycolysis, citric acid cycle, and finally electron transport chain and oxidative phosphorylation. The final result is oxidation of glucose, and reduction of oxygen.. ...


3

ATP is adenosine 5'-triphosphate, a molecule consisting of the base adenine attached to which is attached a ribose (at its 1 position) and (at its 5 position) three phosphates, alpha-, beta- and -gamma (see edited image from Wikipedia below). The (Gibbs) free energy of hydrolysis of the phosphoanydride bonds between the gamma and beta phosphates and betweeen ...


3

For skeletal muscles, you'll find a discussion in the Physics SE: https://physics.stackexchange.com/questions/1984/why-does-holding-something-up-cost-energy-while-no-work-is-being-done To make things short: while holding a position, muscles need to maintain a given length. However, internally, the muscle looks like a collapsible array of filaments, with ...


3

Just to extend the answer from @Amory slightly, I think that the terms active and passive transport are best kept for describing transmembrane movement of molecules. In the case of exocytosis the only transmembrane event is when a secreted protein is first inserted (usually cotranslationally) across the endoplasmic reticulum membrane. I'm not aware of any ...


3

After a quick glance at the book "Light and Photosynthesis in Aquatic Ecosystems" by Kirk (2010), I think that the cause for the productivity dip towards the surface partially lies in photoinhibition, due to high light intensities at the surface. Here are a couple of relevant quotes from the book (Google books: p. 371): In this light saturated state, the ...


3

Table 1 on the next page (p. 36) lists a number of properties for each of the three "growth forms". For information, properties include: Life history types Diversity (taxonomic & ecological) Body size Stability I have to admit that some of these properties doesn't really make sense to me under these headings (at least from the common use of these ...


3

That's an interesting hypothesis - however, I am not aware of any evidence that this is the case. Importantly, there can be a lot of difference between cellular access to energy, like ATP, and the perception of "energy" or liveliness. Here is a paper that actually suggests the opposite: that ADHD could be caused by a neuronal energy deficiency because of ...


3

As far as I know there are two main reasons for this: promoting a nucleophilic attack In general, Mg2+ interacts with substrates through inner sphere coordination, stabilising anions or reactive intermediates, also including binding to ATP and activating the molecule to nucleophilic attack (wiki) - assists in the leaving a pyrophosphate group ...


3

Another reason which might have played a crucial role in preference of adenine could be its greater stability over other nucleobases. Dividing nucleobases into purines (A, G) and pyrimidines (C, T, U), lets first look at the pyrimidines. It is a well established fact that pyrimidines are more prone to damage, especially damage caused by UV radiation. It is ...


3

Your (original) description: a kinase helps chemically deliver or metabolize stored energy within a cell sounds a little more like what many ATPases do: they are using the energy from ATP to do some energetically unfavorable work, such as moving molecules or ions against their concentration gradients. However, kinases have a broad range of different ...


2

Short answer It is known that a great variety of soil micro-organisms is able to use solid anodes as electron acceptor for their metabolism, thus creating some electrical current. Geobacter spp., Clostridia and Deltaproteobacteria are among them (1). However, I could not find any extensive list of these microbes. It is likely that a large number of these ...


2

It is yet to be discovered by scientists. But there is a new study that finds that brain cells called astrocytes supply the urge to sleep by releasing adenosine a chemical known to have sleep-inducing effects. The chemical accumulates in the brain during waking hours, eventually helping to stimulate the unique patterns of brain activity that occur during ...


2

The short answer: no. First, let's get an understanding of the cell cycle control system, as there are some important molecules involved in this system that regulate mitosis. Think of the control system as a series of stoplights: as you mention, there is one stoplight at the G2 phase. There are two additional checkpoints: one at G1 and one in the M (mitotic) ...


2

What you have asked for is a causal answer to correlated findings. There is no cause-effect evidence (at least from my searching) showing low cholesterol will indeed cause stroke. Associations like this are dangerous in the sense that we shouldn't think that one causes the other. But, we can speculate on how they are linked, which is always fun. I'll be ...


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